The U.S. Department of Defense is currently moving toward the long-term goal of insensitive munition-compliant inventory. The acquisition treatment of insensitive munitions was the subject of a Jan. 26, 1999, memorandum from the Under Secretary of Defense for Acquisition, Technology and Logistics. The overall intent of the memorandum was to focus scarce resources on forward fit incorporation of insensitive munition-compliant technology.
Insensitive munition is expected to save lives and material. As defined in STANAG 4439, insensitive munitions mean: “Munitions which reliably fulfill their performance, readiness and operational requirements on demand, but which minimize the probability of inadvertent initiation and severity of subsequent collateral damage to weapon platforms, logistics systems and personnel when subjected to unplanned stimuli.”
“Unplanned stimuli” include thermal and mechanical impact threats of Fast Cook-Off (FCC), Slow Cook-Off (SCO), Bullet Impact (BI), Fragment Impact (FI), Sympathetic Detonation (SD), Shaped Charge Jet (SCJ), and Spall Impact (SI) as presented in MIL-STD-2105B.
The memorandum adds: “All munitions and weapons shall be designed to conform with insensitive munitions (unplanned stimuli) criteria and to use materials consistent with safety and interoperability requirements. Requirements shall be determined during the requirements validation process and shall be kept current throughout the acquisition cycle for all acquisition programs. Interoperability, to include insensitive munitions policies, shall be certified per CJCSI 3170.01A.” “The ultimate objective is to design and field munitions which have no adverse reaction to unplanned stimuli, analogous to Hazard Division 1.6 (TB 700-2/NAVSEAINST 8020.8B/T.O. 11A-1-47/DLAR 8220.1, “Department of Defense Ammunition and Explosives Hazard Classification Procedures”).”
As a result, efforts have been made to render the insensitive munition more amenable to detonation. One such effort is described in U.S. patent application, publication No. 2006/0011083 A1. This publication generally describes methods and compositions for microwave heating of energetic materials. It proposes mixtures for high explosives with materials that absorb microwaves resulting in a net temperature increase and therefore detonate at lower shock pressures when exposed to microwave energy than the corresponding neat explosives.
It would however be desirable to provide other formulations and methods for rendering insensitive munition amenable to detonation of lower shock pressures, and as such change from a relatively shock insensitive formulation to a shock sensitive formulation.